John Lennon's debut at the famous Cavern Club was earlier than that listed by Beatles' historians, a former bandmate has claimed.Rod Davis, who played banjo alongside Lennon in The Quarrymen, says the date of 7 August, 1957 is incorrect.Mr Davis performed in the skiffle group at the club with Lennon, but was on holiday in France in early August 1957."No question about it, I played three or four times at The Cavern and it was definitely before August," he said." I have my dad's passport which says 'Entry to Boulogne 29 July, 1957', so I was definitely not there."